title: A retrospective study of antipsychotic drug switching in a pediatric population.
abstract: BACKGROUND
  Antipsychotic drugs can be used to help treat a wide variety of psychiatric disorders. However, specific antipsychotic drugs for any particular patient may need to be changed for a number of different reasons, including a lack of therapeutic efficacy and / or intolerance to medication side-effects. Drug switching may occur through a limited number of established patterns. The nature of these changes is not well characterized in youth, despite their frequent occurrence.
  
  
  METHODS
  A retrospective analysis of antipsychotic drug switches was conducted on patients who had been admitted as inpatients to a tertiary care child and adolescent psychiatric institute. PharmaNet (a large, central administrative database) records of all medications prescribed in the 52 weeks prior to admission, and then between admission and discharge, were analyzed for switching patterns. Additional data regarding diagnoses were obtained from medical chart review.
  
  
  RESULTS
  Patients represented a diagnostically heterogeneous population, and almost all antipsychotic drugs were administered off-label. In the one year prior to and during admission to the hospital, a total of 31 out of 139 patients switched antipsychotic drugs. The frequency of switching increased closer to the time of admission, and the proportional rate of switching was even higher during hospital stay. The most common switch was from risperidone to quetiapine. Our analysis identified three main patterns of drug switching, all occurring with similar frequency: titrated drug switches, abrupt drug switches and concurrent drug administration.
  
  
  CONCLUSIONS
  The present study indicates that antipsychotic drug switching in youth may be relatively common, particularly in the year prior to hospitalization. No specific manner of drug switching predominates. This study also demonstrates the feasibility of using large administrative databases to characterise switching patterns in youth.
authors.affiliation: British Columbia Mental Health and Addictions Services Research Institute, 938 W 28th Avenue, Vancouver, BC V5Z 4H4, Canada. al.barr@ubc.ca.
authors.forename: David
authors.initials: D
authors.lastname: Linton
authors.forename: Ric M
authors.initials: RM
authors.lastname: Procyshyn
authors.forename: Dean
authors.initials: D
authors.lastname: Elbe
authors.forename: Lik Hang N
authors.initials: LH
authors.lastname: Lee
authors.forename: Alasdair M
authors.initials: AM
authors.lastname: Barr
mesh_terms: D000293:Adolescent; D014150:Antipsychotic Agents / Q000627:therapeutic use*; D002648:Child; D016208:Databases, Factual; D057915:Drug Substitution; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000188:drug therapy; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents